HEAT SHOCK PROTEINS AND CANCER

CIOCCA DR; CAYADO GUTIÉRREZ N.

Mendoza

Congreso; XXVIII Reunión Anual de la Sociedad de Biología de Cuyo; 2010

Sociedad de Biología de Cuyo

In 1962 F. Ritossa was studying the giant polythene chromosome in larvae of Drosophila melanogaster and described for the first time chromosome puff caused by a mild temperature rise. Latter it was found that this puff indicative of gene activity, specifically DNA and RNA synthesis, caused the induction of a group of proteins known as heat shock proteins (Hsps, given name due to the first stimulus).Today we now that the Hsps belong to a large family of proteins characterized by their molecular weights, having in common molecular chaperone abilities and cytoprotection. In cancer, the Hsps induced by cell stress like hypoxia, acidosis) are overexpressed in a wide range of tumors, moreover the increased transcription of Hsps may be due to loss of p53 function and to higher expression of the protooncogenes Her2 and c-Myc. The Hsp family members play overlapping, essential roles in tumour growth both by promoting autonomous cell proliferation and by inhibiting death pathways; therefore they can be associated with a poor prognosis and resistance to therapy. Hsps can be targets for anticancer drugs. In addition, several of the Hsps have important roles in the immune response, they display an innate ability to function as biological adjuvants and to chaperone tumour antigens creating an opportunity for cancer immunotherapy.